Many exercise and recreational centers are now equipped with simulated climbing walls. Devices of this type include both larger, stationary structures as well as more compact “endless walls.” Conventional endless wall climbers consist of large linked panels dressed over upper and lower rollers. The panels have an outer surface with hand-holds or other features that a user ‘climbs’ as the panels rotate.
A drawback of typical linked-panel type climbers is that the rollers are motor-driven, resulting in a piece of equipment which is heavy and expensive to purchase and operate. As such, there have been attempts to provide non-motorized, self-regulating machines. One such piece of equipment is disclosed in U.S. Pat. No. 5,125,877 entitled “Simulated Climbing Wall.” This prior-art unit is comprised of a frame, at least two guide members rotatably attached at the top of the frame, and a plurality of climbing wall panels, each being flexibly attached to the next in a continuous chain. The chain structure is adjustable such that the panels may be moved downwardly in a controlled manner as the climber climbs.
In operation, the apparatus of the '877 patent uses an automotive rear axle assembly differential unit including two wheels and brakes. The wheels support the weight of the articulated wall structure and allow the articulated wall structure to move down under the weight of the climber, when the brakes are released. The brakes are normally on and are released when the climber passes a predetermined height on the wall. When the climber passes the predetermined height, a rope attached to the climber's waist through a carabineer becomes taut and lifts a weight, thereby releasing the brake and allowing the panels to move downwardly under the weight of the climber. When the user descends to a sufficient level, the brakes once again engage, allowing the user to ascend the wall.
Another self-regulating device is disclosed in U.S. Pat. No. 5,328,422, entitled “Ladder-Climbing Exercise Device.” This system includes an inclined flight along which a plurality of rungs are presented in an endless manner. The marginal ends of the rungs are mounted on endless chains which are supported by a frame. The chains are coupled to a fan having a squirrel cage-like rotor. The position of an operator relative to the flight changes the size of a fan aperture to vary the resistance afforded by the device to the climbing motion.
Although these and other prior-art systems attempt to regulate climbing motion without the use of electricity, there nevertheless remain heavy and/or complex. The need therefore remains for a simple, elegant and effective self-regulating endless wall-climbing structure.